While vent-free gas logs don’t burn as high as vented logs, they make up for their lack of flash with less pollution and more heat. Sometimes referred to as “vent-free heaters,” ventless gas logs don’t require an open chimney, meaning that 100% of the heat generated is kept in your home – and to top it off, ventless logs use less gas, saving you money not only in heating, but also in your gas line.